From 32b7c9a433930842533064d829ba214aadf6a67d Mon Sep 17 00:00:00 2001 From: phk Date: Sat, 21 Feb 2004 20:29:52 +0000 Subject: Device megapatch 2/6: This commit adds a couple of functions for pseudodrivers to use for implementing cloning in a manner we will be able to lock down (shortly). Basically what happens is that pseudo drivers get a way to ask for "give me the dev_t with this unit number" or alternatively "give me a dev_t with the lowest guaranteed free unit number" (there is unfortunately a lot of non-POLA in the exact numeric value of this number, just live with it for now) Managing the unit number space this way removes the need to use rman(9) to do so in the drivers this greatly simplifies the code in the drivers because even using rman(9) they still needed to manage their dev_t's anyway. I have taken the if_tun, if_tap, snp and nmdm drivers through the mill, partly because they (ab)used makedev(), but mostly because together they represent three different problems for device-cloning: if_tun and snp is the plain case: just give me a device. if_tap has two kinds of devices, with a flag for device type. nmdm has paired devices (ala pty) can you can clone either of them. --- sys/dev/snp/snp.c | 30 ++++++++++++------------------ 1 file changed, 12 insertions(+), 18 deletions(-) (limited to 'sys/dev/snp') diff --git a/sys/dev/snp/snp.c b/sys/dev/snp/snp.c index 4c4115d..2c1c3c6 100644 --- a/sys/dev/snp/snp.c +++ b/sys/dev/snp/snp.c @@ -38,7 +38,6 @@ static d_write_t snpwrite; static d_ioctl_t snpioctl; static d_poll_t snppoll; -#define CDEV_MAJOR 53 static struct cdevsw snp_cdevsw = { .d_open = snpopen, .d_close = snpclose, @@ -47,7 +46,7 @@ static struct cdevsw snp_cdevsw = { .d_ioctl = snpioctl, .d_poll = snppoll, .d_name = "snp", - .d_maj = CDEV_MAJOR, + .d_flags = D_PSEUDO, }; static struct linesw snpdisc = { @@ -101,10 +100,9 @@ static MALLOC_DEFINE(M_SNP, "snp", "Snoop device data"); * module load time. */ static int snooplinedisc; -static udev_t snpbasedev = NOUDEV; - static LIST_HEAD(, snoop) snp_sclist = LIST_HEAD_INITIALIZER(&snp_sclist); +static struct clonedevs *snpclones; static struct tty *snpdevtotty(dev_t dev); static void snp_clone(void *arg, char *name, @@ -384,9 +382,7 @@ snpopen(dev, flag, mode, td) struct snoop *snp; if (dev->si_drv1 == NULL) { - if (!(dev->si_flags & SI_NAMED)) - make_dev(&snp_cdevsw, minor(dev), UID_ROOT, GID_WHEEL, - 0600, "snp%d", dev2unit(dev)); + dev->si_flags &= ~SI_CHEAPCLONE; dev->si_drv1 = snp = malloc(sizeof(*snp), M_SNP, M_WAITOK | M_ZERO); snp->snp_unit = dev2unit(dev); @@ -466,6 +462,7 @@ snpclose(dev, flags, fmt, td) free(snp->snp_buf, M_SNP); snp->snp_flags &= ~SNOOP_OPEN; dev->si_drv1 = NULL; + destroy_dev(dev); return (snp_detach(snp)); } @@ -608,20 +605,18 @@ snp_clone(arg, name, namelen, dev) int namelen; dev_t *dev; { - int u; + int u, i; if (*dev != NODEV) return; if (dev_stdclone(name, NULL, "snp", &u) != 1) return; - *dev = make_dev(&snp_cdevsw, unit2minor(u), UID_ROOT, GID_WHEEL, 0600, - "snp%d", u); - if (snpbasedev == NOUDEV) - snpbasedev = (*dev)->si_udev; - else { + i = clone_create(&snpclones, &snp_cdevsw, &u, dev, 0); + if (i) + *dev = make_dev(&snp_cdevsw, unit2minor(u), + UID_ROOT, GID_WHEEL, 0600, "snp%d", u); + if (*dev != NULL) (*dev)->si_flags |= SI_CHEAPCLONE; - dev_depends(udev2dev(snpbasedev, 0), *dev); - } } static int @@ -642,8 +637,7 @@ snp_modevent(mod, type, data) if (!LIST_EMPTY(&snp_sclist)) return (EBUSY); EVENTHANDLER_DEREGISTER(dev_clone, eh_tag); - if (snpbasedev != NOUDEV) - destroy_dev(udev2dev(snpbasedev, 0)); + clone_cleanup(&snpclones); ldisc_deregister(snooplinedisc); break; default: @@ -657,4 +651,4 @@ static moduledata_t snp_mod = { snp_modevent, NULL }; -DECLARE_MODULE(snp, snp_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE + CDEV_MAJOR); +DECLARE_MODULE(snp, snp_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE); -- cgit v1.1